Valve mechanism fob engines



. B. MCNAIR.

VALVE MECHANISM FOR ENGINES.

APPLiCAlON FILED FEE. 27. 1918.

Fatened Dec. 3G,1919.

II'YT'ESSES W. B. MCNIR.

VALVE MECHANISMFOR ENGINES.

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UNITED STATES PATENT oFFroE.

WILLIAM BURNS VCNAIR, JF HARRISBURG, PENNSYLVANIA.

VALVE MECHANISM FOR ENGINES.

Application ledlebruary 27, 1918.

and exact description of the invention1 such as will venable others skilled in the art to .which it appertains to make and use the sam Txis invention relates to improvements in valve mechanism and more particularly to such as are adaptable for use with internal combustion engines,*one object ot' the invention being to provide a simple valve structure of the rotary valve type, in which longitudinal displacement of the valve shall be prevented; to guard against leakage at the ports, and to insure the smooth and effective operation of vsaid valve.

lVith this and other objects in view, the invention consists in certain novel featmfes of construction and combinations of parts as hereinafter set forth and pointed om. in the claims.`

In the accompanying drawings; Figure l -is a transverse vertical sectional view ot an engine showing an embodiment ot my inveutionz Fig. 2 is a horizontal sectional view; Fig. 3 is an enlarged sectional view showing the inlet valve and its mountings; Fig. -t is an enlarged detail view vof a portion of the bushing and showing packing means for the ports and Fig". 5 is an enla rged sectional View of the inlet valve tube.

.l represents an engine casingcomprisingT a cylinder Q'having a piston 3 therein, and a crank pit 4:, in which latter the crank shaft 5 is mounted and connected with the piston by means otl a pitnian (i, as is well understood.

A head 7 is secured to one end ot' the engine easing by means of bolts .The end of the engine casingr is made with seats vi) which iorm halfdnmrings for the rotary valve mechanisms hereinafter desmilled,"4 the other half-portionslof said bearings being formed by concave bars 1l! mounted in recesses l1 in the head 7. ln Figs. l and 2, the inlet valve is represented at 12 and the exhaust valve at 13,-the latter being' preferably somewhat greater in diameter than the valve 12.

The inlet valve 12 is made in the r'orm Specification of Letters Patent.

Patented Dec. 30, 1919.

Serial No. 219,488.

of a single tube closed at both ends an'd provided with a plurality of'ports 14 to communicate in proper succession with the several cylinders 2 shown in Fig. 1,-and'the valve tube is provided at intervals with annular flanges 15 v(said flanges preferably alternating with'the ports 14) which rotate in suitable grooves or recesses formed in the seat .9 and bearing bar 10 to prevent longitudinal displacement of the valve tube. The exhaust valve tube 13 is similarly provided with annular flanges 15 to rotate in grooves or recesses for the same purpose. The exhaust valve tube is closed at one end and open at the other` end and it is provided with suitable ports, such as shownrat 16 to permit the escape ot' exhaust products of ron'ilnlstion from the cylinders. The valves 1i). and 13 are inclosed by bushings 17 disposed between the annular flanges 15 and each ot said bushings is made in at least two parts as shown in Fig. 1 and seated in the seats J and bearing bars 10. To compensate for wear and to properly hold the bushings in place, set screws 18 are provided,-said set screws passing through the head '7 and engaging the bearing bars, 'and suitable jam nuts 19 on said screws will serve to retain the latter -in the position to which they may be adjusted.

A chamber cO surrounds the central portion of the inlet valve tube 12 and Comnniuieales theren-'ith through ports 21 so that explosive mixture supplied to said chamber from a suitable source, will flow iu both directions in said tube and find its way to the cylinders through the ports 14 as the latter are successively opened. The bushings ol each ot' the valve tubes are recessed addiarent to the ports 22 therein tor the aeeoimnodation ot packing frames 23 which surround said ports and these packingl frames are pressed against the valve tube b v springs 24; located behind the packiner l'ran'ies in the Yrecesses of the bushings.

lhe two valvetubes are rotated continuously by a hoist-less drive rhaiu 2.5 which receives motion from a' sprocket wheel '26 on the crank shatt- 5 and passes over sprocket wheels QT, QS, secured to the respective valve tubes. This chain may also be utili'lgv'al to marry lunieant up jfrom the rrank pit and deliver it thronghthe medium of a trough il() to lulivrioating ducts 2f) disposed under the respective valve bushings for supplying' lubricant to the valves.

Various slight changes might be. made in the details of construction of my invention without departing from the spirit thereof or limitinvr its scope and hence Li. do not wish to restrict myself to the precise details herein set forth.

Having fully described my invention what I claim as new and desire .to secure b v Let-- ters-Patent, isz-- 1. The combination with an engine havingl e Valve seat in its casing, of a rotar)T tubular valve having circumferential flanges mounted on said seat, segmental bushings encircling the valve tube between said tlan ges and also mounted on said seat, a recessed member over said valve and engaging said bushil'igs, said valve having ports to com# niunieate with the cylinders of the engine, and means for rotating said valve. v

2. The combination with an engine ha ving a valve seat in its casing, and a recessed head. of a rotary tubular valve having circumferential flanges, mounted ou said scat, segmental bushings encirclingY the 'alve tube between said ilanges and also mounted on said seat, recessed. bars in the recessed hea'd of the casing' and engaging both segments of said bushings, said valve having ports to communicate with the cvlii'iders of the engine, and means for rotating said valve.

3. In an engine, the combination with the casing and a recessed head secured thereto,

Isaid casing having-j a seat at one end.l of a har n'iovable in said recessed head and havirrer a seat, said seats having transverse grooves, el. a rotary valve disposed between said seats and having circumferential flanges to enter the transverse grooves in said seats, segmentalhushings surrouinling said rotary valve between the circumferential ianges, the bar in the recessed head engaging both segments 0i each bushing, and an adjusting screvv passing through the engine head and engaging said bar.'

4. rIhevconibination with an engine comprising a casing, a cylinder, a piston, a crank shaft connected with the piston, and a crank pit, of rotar)7 inlet iVlLLlAM BURNS MGNAIR. Witnesses Lno Grenen MARTXN, EMXUEL L. HAINES.

and exhaust valves mounted in the casing, said easing` 

